What causes autism?

There is no simple answer as to why autism occurs. It is an area still being extensively researched. This resource is intended to give an overview of what we do and do not know about the causes of autism, and the issues that arise from this.

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The different types of autism

Autism is a spectrum condition. This means that it can have very different impacts on the lives of different autistic people. There is no single effect of autism that is common to all or even most autistic people.

Many of the distinctions that some try to draw between different “types” of autism are unhelpful and can be damaging and offensive. Can you tell where red becomes orange on a rainbow, and does it matter anyway – both are beautiful in their own right. So talking about “high-functioning” and “low-functioning” autism is both meaningless and can be offensive, just as it would be to talk about high or low functioning people generally.

All autistic people are different just as all people are different and excel in some areas while possibly needing more help and support in others.


Current research into possible causes

It is important to remember that there is a great deal of research going on into how the brain works in general, with much still not properly understood about how we think, remember, have ideas and so on. As autism can be characterised as the brain working differently, or even being wired differently, research into its causes is inextricably linked to our understanding of how the brain works at all.

There primary area being investigated as a possible cause of autism is genetics. In families where one person is autistic, other family members often are too, so there does appear to be a genetic aspect to autism.

A number of genes have been identified as being associated with autism, but there has no “autism gene” identified that is the whole and only cause of being autistic. Many of the genes found to be associated with autism are related to the way that neurons in the brain use chemicals to connect with each other, which makes perfect sense in terms of autistic brains working differently. As with all areas of genetics, there is much still to be explored in this research.

Environmental factors are also being investigated as possible contributing factors to autism alongside genetics. These are not things within the control of parents, but factors such as being born prematurely or having a difficult birth, which have been shown to lead to an increased occurrence of autism. It is not yet known precisely what it is about these events that can lead to autism, but it is thought to be related to differences in the development of the brain.

Once again, it is important to emphasise that these factors cause autistic people to be different, not to be sick or to have anything wrong with them. Genetics also contribute to us having different hair colours, different shaped noses and different tones of voice, none of which are considered diseases or disorders either!

Myths around the causes of autism

There are several common myths about the causes of autism. As well as being untrue, these are based on the premise that autism in a bad thing. Once you realise that autism is a difference rather than a disease or something to fear, these myths and scaremongers lose all power anyway.

Perhaps the most widespread myth is that autism can be caused by certain vaccinations, such as the MMR. This is completely untrue, and the scientific study that gave rise to this belief has been widely discredited. There is no evidence at all that there is a connection between any vaccine and autism. On the contrary, vaccines are an important part of healthcare and disease prevention, and you should always follow the recommendations of your healthcare provider.

Other myths are that autism can be caused by bad parenting in some form, is infectious or can be caused by certain diets. Again, there is no evidence whatsoever to support any of these suggestions – autism in a child cannot be blamed on actions or inactions of the parents in any way and is not something that requires any blame to be apportioned at all.


Treatment for autism

As previously noted, autism is not a disease to be cured. The biggest issues faced by many autistic people arise from the world being organised for a different way of thinking, such as noisy work environments and brightly lit areas, or insistence on face-to-face communication when a text-based alternative would work better for the autistic person. These issues can normally be addressed by adjustments to environments or ways of doing things.

Some aspects of autism can be helped with therapies, such as slow development of speech in autistic children. There are a number of strategies that can be used to encourage non-verbal autistic children to speak or communicate in other ways, such as by using communication devices and apps such as app2vox.

Where mental illness accompanies autism, as sadly is often the case due to the pressures of living as an autistic person in a neurotypical world, medication and therapies may be of assistance.

Perhaps the biggest help for autistic people is to talk with other autistic people and realise that they are not alone in facing the challenges they come up against. The autistic community is hugely supportive, and the availability of online communication makes it much easier to contact others in a similar situation to your own, or to connect with other parents of autistic children.


How autism changes with age

The impact of autism on someone’s life can change as the person grows older, just as we all change as we grow older. For example, children that have little or no speech when young may develop more verbal skills later so that by the time they are teenagers they are similar to their peers in this respect.

One thing that does impact many autistic people as they age is a greater sense of self-awareness with age and a better understanding of what autism is and is not. A diagnosis can have a huge impact, particularly when received in adulthood as it can explain many difficulties faced earlier in life.

Recognising that you are autistic, and that there is nothing wrong with being autistic, can sometimes bring greater self-acceptance into a troubled life, and then going on to access support from other autistic people and realise that you are far from alone can also be a huge help.

How to get a diagnosis

The first step in seeking a diagnosis for autism is to speak to your doctor or another health professional, or possibly to a special needs teacher for a school age child. The process can take some time to complete and there may be a significant waiting list.

A diagnosis normally involves conversations with the person themselves and possibly also with family, friends and teachers if appropriate. When approaching a diagnosis, it can be helpful to make some notes about why you believe that you may be autistic and the issues that are arising in your life as a result. Be prepared to persevere and keep pushing for an assessment if you believe that you need it!

More information on getting a diagnosis in the UK can be found on the NHS website here.


The causes of autism are likely to be largely genetic but are not fully understood. Autism is not caused by vaccines, parenting style, diet, or any other factors in anyone’s direct control. However, autism should not be seen as a bad thing but as a difference, and with accommodations and adjustments autistic people can and do live rich and fulfilling lives.

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